This invention relates to a circulation type combustion means adapted to permit circulation of combustion gas.
Generally, means for combustion requires a flame-retaining device capable of stabilizing the flame. Most flame-retaining mechanisms are so devised as to provide desired stability of combustion flame by causing a backflow region of combustion gas to be formed close to the fuel discharge nozzle.
Of the flame-retaining devices which find general acceptance, those which enjoy satisfactory performance of flame-retaining mechanisms have the flame formed in the neighborhood of the fuel discharge nozzle. Since the neighborhood of the fuel discharge nozzle is consequently susceptible to superheating, such flame-retaining devices inevitably entail various attendant drawbacks. In the case of the flame-retaining devices adapted to have the flame formed at an appropriate distance from the fuel discharge nozzle, a region capable of forming a flame occurs in the space between the fuel discharge nozzle and the zone of flame. These devices, therefore, suffer from a disadvantage that said flame zone is not stabilized and tends to produce a phenomenon of vibrated combustion.
An object of the present invention is to provide a gas combustion means which precludes the possibility of exposing the neighborhood of the fuel discharge nozzle to superheating and which produces a stable flame at a fixed distance from the fuel discharge nozzle without entailing the phenomenon of vibrated combustion.